Yes. Of course. Most of the problems with Wordpress websites are because of bugs in programs written in PHP. When you no longer serve PHP and are just serving a bunch of HTML/CSS files then there is nothing left to hack. (unless you want to target the webserver [such as Apache, etc.) but 9/10 times it is some sort of an outdated software or just some previously unknown bug in some plugin. Less attack surface, more peace of mind.